Deadline reports that she died from breast cancer complications. Wallace was originally diagnosed with breast cancer in 1985 and worked as an advocate for breast cancer survivorship.

Wallace rose to fame as receptionist Carol Kester on The Bob Newhart Show in the 1970's. But her one of her most recent roles was the voice of teacher Edna Krabappel in The Simpsons.

The Simpsons executive producer Al Jean told ABC News Radio that Wallace's "irreplaceable character" would be retired from the show.

"When you grow up watching some shows like The Bob Newhart Show you go, 'I really wish I could meet those characters.' And when you met Marcia, you got exactly what you hoped for. She was hilarious and sweet, very down to earth, extremely friendly," Jean said.

Jean said Wallace will not only be remembered for her TV roles, but also for the inspiring way she battled cancer.

"You would never know that she had any problems talking to her. She was always so fun and upbeat and is a tremendous inspiration," Jean said. "When people say someone was loved by all, in her case, it's not a cliche, it's true."